Seat attachment device

ABSTRACT

A seat attachment device is provided that uses a single bolt to secure the seat rails to the seat attachment device and the seat attachment device to a post.

FIELD OF THE INVENTION

The invention relates generally to a seat attachment device for atransportation device, such as a bicycle.

BACKGROUND OF THE INVENTION

Most modern bicycles have a seat attachment device that inserts into theframe of the bicycle and may be tightened in order to secure a saddlefor the bicycle to the frame of the bicycle. A conventional bicycle seatassembly 80 is shown in FIGS. 1 and 2 and generally includes a seat 81,a post 82 and a securing device for connecting the seat 81 to the post82. The securing device includes a top bracket 84 connected to theunderside of the seat 81 and a lower bracket 85 which is fixed on a topof the post 82. Two rails 83 are clamped between the top bracket 84 andthe lower bracket 85. Two bolts 86 extend through two transverse barsconnecting the top bracket 84 and the lower bracket 85 to pull the topbracket 84 and the lower bracket 85 toward each other so that the tworails 83 are securely clamped. It is noted that the two bolts 86 arethreaded through the two bars from in top bracket 84 so that it isdifficult to adjust the angle of the seat relative to the post 82. Inaddition, the shocks from the roads are transferred along the post 82 tothe seat 81 and the direction that the shocks are transferred is thesame as the bolts 86 which are easily loosened by the shocks. Thus, itis desirable to provide a seat attachment device that overcomes theselimitations of the current seat attachment device and it is to this endthat the present invention is directed.

SUMMARY OF THE INVENTION

A seat attachment device is provided in which the seat attachment deviceis lightweight and uses a minimal amount of structure to secure a saddleto a bicycle. The seat attachment device permits easy adjustment of theseat attachment device (and the seat secured by the seat attachmentdevice) relative to the post. The seat attachment device has first andsecond outer clamps wherein each outer clamp has a channel region inwhich a seat rail may be positioned when the seat attachment device isassembled. The outer clamps also have a bore through which a securingmechanism, such as a bolt, is passed in order to secure the pieces ofthe seat attachment device together and a chamfered surface which ispressed against the post to affix the pieces of the seat attachmentdevice together. For each outer clamp, the channel region is above thebore through which the securing mechanism is passed and the bore isabove the chamfered surface.

Thus, in accordance with the invention, a seat attachment device isprovided wherein the seat attachment device has a post and an innerclamp mechanism that is positionable on the post and has a channelregion. The seat attachment device also has a first outer clamp that hasa channel region and a chamfered surface that is beneath the channelregion and a second outer clamp that has a channel region and achamfered surface that is beneath the channel region. The seatattachment device also has a securing mechanism that presses thechamfered surface of the first outer clamp against a first side of thepost and the chamfered surface of the second outer clamp against anopposite side of the post wherein the channel regions of the inner clampmechanism and the first and second outer clamps form a channel intowhich a seat rail may be positioned to secure the seat rail to the seatattachment device.

In accordance with another aspect of the invention, an outer clamp for aseat attachment device is provided. The outer clamp has a channel regioninto which a seat rail may be positioned and a bore, located underneaththe channel region, through which a securing mechanism may be passed.The outer clamp also may have a chamfered surface, located below thebore, that may be pressed against a post in order to secure the outerclamp to a post of a seat attachment device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a prior art seat attachment device;

FIG. 2 illustrates another view of the prior art seat attachment device;

FIG. 3 illustrates an example of an embodiment of a seat attachmentdevice;

FIG. 4 illustrates more details of the seat attachment device shown inFIG. 3;

FIGS. 5A-D are diagrams illustrating more details of the seat attachmentdevice shown in FIGS. 3 and 4;

FIG. 6 is a cut-away view of the seat attachment device shown in FIGS. 3and 4;

FIG. 7 illustrates an example of another embodiment of the seatattachment device;

FIG. 8 illustrates an example of another embodiment of the seatattachment device;

FIG. 9 illustrates an example of another embodiment of the seatattachment device;

FIG. 10 illustrates an example of another embodiment of the seatattachment device; and

FIGS. 11A and B illustrate two examples of a single piece inner clampmechanism.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

The invention is particularly applicable to a seat attachment deviceimplemented as set forth in the following diagrams and figures and it isin this context that the invention will be described. It will beappreciated, however, that the seat attachment device in accordance withthe invention has greater utility since it may be implemented indifferent manners and may also be used to secure a seat or saddle incontexts other than a bicycle saddle. For example, the seat attachmentdevice may be constructed out of different materials that thosedescribed below and be within the scope of the invention or the seatattachment device may be used for an application other than securing asaddle to a bicycle and those other applications are within the scope ofthe invention.

FIGS. 3 and 4 are diagrams illustrating an example of an embodiment of aseat attachment device 10 that secures a saddle 11 (shown in phantom inFIG. 3) to a post 12. The seat attachment device comprises first andsecond inner clamps 14,16 (that may be collectively known as an innerclamp mechanism) and first and second outer clamp 18, 20 wherein thefirst inner and outer clamps 14, 18 and the second inner and outerclamps 16, 20 each form a channel 22 into which the rails of a seat maybe positioned and secured when a securing mechanism 24, such as a boltin one embodiment, is passed through the first outer clamp 18 and secondouter clamp 20 and tightened. In the example of the seat attachmentdevice shown in FIGS. 3 and 4, the first inner clamp 14 and second innerclamp 16 are maintained at a predetermined distance from each otherusing a mechanism 26 that is attached over a post member 28 that is partof each inner clamp. However, the seat attachment device 10 inaccordance with the invention may be implemented without the mechanism26 and without the post members 28 that are shown in FIGS. 3 and 4. Forexample, a one piece inner clamp mechanism may be used. In the seatattachment device shown in FIGS. 3 and 4, the securing mechanism islocated below the channels 22 into which the seat rails are placed andabove a tapered/chamfered surface of the outer clamps 18, 20 (shown inFIG. 5D) that will be described in more detail below. The location ofthe securing mechanism relative to the channel 22 and the surfaces ofthe outer clamps results in the seat attachment device (with only thesingle securing mechanism 24) being able to exert sufficient force tohold the seat rails in the channels and also releasably secure the seatattachment mechanism 10 to the post 12. The seat attachment device 10 inaccordance with the invention minimizes the material and structurerequired to hold the seat rails of a saddle which reduces the overallweight of the seat attachment device without sacrificing strength.

FIGS. 5A-D are diagrams illustrating more details of the seat attachmentdevice shown in FIGS. 3 and 4. FIG. 5A shows the seat attachment device10 when it is assembled and FIG. 5B illustrates a side view of the seatattachment device 10. FIG. 5C is a cross sectional view of the seatattachment device 10 and FIG. 5D is an assembly diagram of the seatattachment device 10. As shown in FIG. 5D, the seat attachment device isassembled by placing the inner clamps 14, 16 onto a head portion 32 ofthe post 12, placing the outer clamps 18,20 into their respectivepositions and then inserting the securing mechanism 24 through the outerclamps and tightening the securing mechanism. To secure a seat with seatrails to the post 12, the securing mechanism 24 is loosened sufficientlyto permit the seat rails to be placed into the channels 22 of the seatattachment device and then the securing mechanism is tightened.

As shown in FIGS. 5C and 5D, for this embodiment, each outer clamp 18,20 has an interface surface 30, that may be a chamfered surface in thisembodiment, that, when the seat attachment device is assembled, pressesagainst an interface surface 31, such as a tapered surface in thisembodiment, of the post 12 to releasably secure the seat attachmentdevice 10 to the post 12. Thus, the seat attachment device 10 is securedtogether and to the post (and secures the saddle to the seat attachmentdevice) using a single securing mechanism 24 and interface surfaces 30,31 of the outer clamps 18, 20 and the post 12. The chamfered surface 30is pressed against the tapered portion 31 of the post 12 when the seatattachment device 10 is assembled together. The outer clamps 18, 20 thusreleasably secure both the seat attachment device 10 to the post 12 andthe saddle 11 to the seat attachment device 10 and the post 12. In theexemplary embodiment shown in these figures, the post 12 has a headportion 32 that is shaped with curved portions so that the inner clamps14, 16 can rest on the head portion 32 of the post 12 and the chamferedsurface 30 of each outer clamp 18, 20 can be pressed against the taperedportion 31 of the post 12.

FIG. 5D also illustrates that the seat attachment device 10 can be movedrelative to the head portion 32 when the securing mechanism 24 is nottightened so that the angle of the seat attachment device 10 (andtherefore the seat rails and the seat that is secured by the seatattachment device) relative to the post 12 can be angularly adjusted. Toadjust the seat angle relative to the post 12, the securing mechanism 24is loosened somewhat so that the outer clamps 18, 20 can slide along thetapered surface 31 of the head 32 which changes the angle of the seatattachment mechanism 10 relative to the post 12. When the desiredadjustment is made, the securing mechanism 24 is again tightened so thatthe chamfered surfaces 30 of the outer clamps 18, 20 are pressed againstthe tapered portion 31 of the head 32 of the post 12 to again secure theseat attachment mechanism 10 and the seat to the post 12.

As can be seen in FIG. 5D, the securing mechanism 24 does not passthrough the inner clamps 14, 16 and in fact the inner clamps rest on topof the head portion 32 of the post 12. In a preferred embodiment shownin FIGS. 5A-5D, the securing mechanism may be a steel bolt while thepost 12, inner clamps 14,16 and outer clamps 18,20 may be made ofaluminum and the mechanism 26 may be an O-ring that is made out of aplastic material. The invention, however, is not limited to thematerials set forth above since the post 12 may also be made oftitanium, carbon fiber/aluminum or carbon fiber and the other componentsof the seat attachment device may be made out of other materials. Inaddition, although the inner clamps 14, 16 are separate pieces, they canbe combined into a single piece. Additionally, the clamps 14-20 may bemade of carbon fiber material with an aluminum insert at locations wherethe compression strength of aluminum is needed, such as in the channelregions of the clamps and on the chamfered surface. In accordance withthe invention, the seat attachment device may also be modified to makeit less expensive to manufacture such as using a one piece inner clampstructure or knurling certain surfaces of the seat attachment device 10.FIG. 6 is a cut-away view of the seat attachment device 10 shown inFIGS. 3 and 4 wherein a pair of seat rails 25 are secured to the seatattachment device 10 and the seat attachment device 10 is secured to thepost 12 by the chamfered surface 30 and the tapered portion 31 beingpressed together as the securing mechanism 24 is tightened.

FIG. 7 illustrates an example of another embodiment of the seatattachment device 10. In this embodiment of the seat attachment device,like elements have the same reference numeral and perform the samefunction as described above. In this embodiment, the securing mechanism26 may be a spring as shown instead of the O-ring shown in the previousembodiment. FIG. 8 illustrates an example of another embodiment of theseat attachment device 10. In this embodiment, like elements have thesame reference numerals as above. In the embodiment shown in FIG. 8,each outer clamp 18, 20 has the interface surface which may be a knurledsurface 50 (or teeth) instead of the chamfered surface in theembodiments shown above. In this embodiment, the outer clamps may bemade of a harder material, such as steel or an alloy, so that the teethor knurled surface can be forged into the outer clamps 18, 20. In thisembodiment, the seat attachment mechanism 10 is releasably secured tothe post 12 when the teeth 50 of the outer clamp 18, 20 are pressedagainst the tapered portion 31 of the post 12 to secure the seatattachment device 10 to the post 12. As with the other embodiment, theangle of seat attachment device 10 (and therefore the seat rails andseat) relative to the post 12 may be adjusted by loosening the securingmechanism 24, adjusting the clamps position 14-20 on the head 32 andthen retightening the securing mechanism.

FIG. 9 illustrates an example of another embodiment of the seatattachment device 10 wherein each outer clamp 18, 20 has the interfacesurface which is a shoulder region 52 in this embodiment and the post 12has the interface surface that is a pair of shoulder regions 54 in thisembodiment. When the seat attachment device 10 is assembled and thesecuring mechanism 24 is tightened, the shoulder regions 52, 54 arepress fit into each other to releasably secure to the seat attachmentdevice 10 to the post 12. In order to ensure that the shoulder regions52, 54 do not slip with respect to each other, the outer clamps 18, 20and/or post 12 may have knurling on the shoulder regions 52 or 54 toprovide more resistance to sliding when the outer clamps 18,20 and post12 are press fit together. As with the other embodiments, the angle ofthe seat attachment device 10 relative to the post 12 may be adjusted byloosening the securing mechanism 24.

FIG. 10 illustrates an example of another embodiment of the seatattachment device 10. In this embodiment, the outer clamps 18, 20 havethe shoulder regions 52 and the post 12 includes the shoulder regions54. In addition, an inner portion 55 of the head portion 32 of the post12 may further comprise knurling or teeth (teeth are shown in FIG. 10)and an underside region 56 of the inner clamps 14, 16 may also furthercomprise knurling or teeth (wherein teeth are shown in FIG. 10.) Theteeth on both the head portion 32 and the inner clamps 14,16 permit theangle of the seat attachment device 10 relative to the post 12 to beadjusted to a plurality of positions wherein each position exists whenthe teeth of the inner clamps 14, 16 are locked into the correspondingteeth of the head region 32 of the post 12.

FIGS. 11A and B illustrate two examples of a single piece inner clampmechanism 60. As discussed above, the inner clamp mechanism may beformed from a single piece as shown in FIGS. 11A and B so that themechanism 26 and the post members 28 are not part of this single pieceinner clamp 60. The single piece inner clamp mechanism 60 may furthercomprise a set of members 62 (shown as either a curved set of pieces inFIG. 11A or a straight set of pieces with a bend in FIG. 11B) thatconnect the first and second inner clamps 14, 16 thus forming a singlepiece. The set of members 62 may be formed as a single piece with thefirst and second inner clamps 14, 16 or may be formed separately andthen secured to the first and second clamps 14, 16. The set of members62 is preferably made of a material with some flexibility and/or memory,such as aluminum or steel or plastic, so that the set of members absorbthe force and energy (compress) when the seat attachment mechanism istightened by the securing mechanism 24 and then release the energy(uncompress) when the securing mechanism 24 is loosened and return totheir uncompressed state.

While the foregoing has been with reference to a particular embodimentof the invention, it will be appreciated by those skilled in the artthat changes in this embodiment may be made without departing from theprinciples and spirit of the invention, the scope of which is defined bythe appended claims.

1. A seat attachment device, comprising: an inner clamp mechanism thatis positionable on a post and has a channel region; a first outer clampthat has a channel region and an interface surface that is beneath thechannel region; a second outer clamp that has a channel region and aninterface surface that is beneath the channel region; and a horizontalsecuring mechanism that, when the horizontal securing mechanism istightened, presses the interface surface of the first outer clampagainst a first side of the post and the interface surface of the secondouter clamp against an opposite side of the post to create a force tohold the seat attachment device to the post and forms a channel from thechannel regions of the inner clamp mechanism and the first and secondouter clamps into which a seat rail may be positioned to secure the seatrail to the seat attachment device.
 2. The seat attachment device ofclaim 1, wherein the interface surface of the first and second outerclamps each comprises a chamfered surface.
 3. The seat attachment deviceof claim 2, wherein the post has a first tapered surface and a secondtapered surface on an opposite side of the post from the first taperedsurface wherein the first and second tapered surfaces of the post arepress fit against the chamfered surfaces of the first outer clamp andsecond outer clamp in order to releasably secure the seat attachmentdevice to the post.
 4. The seat attachment device of claim 2, whereinthe first outer clamp farther comprises a bore through which thehorizontal securing mechanism is passed when the seat attachment deviceis assembled, the bore being below the channel region and above thechamfered surface and wherein the second outer clamp further comprises abore though which the horizontal securing mechanism is passed when theseat attachment device is assembled, the bore being below the channelregion and above the chamfered surface.
 5. The seat attachment device ofclaim 4, wherein the horizontal securing mechanism further comprises abolt.
 6. The seat attachment device of claim 5, wherein the bolt furthercomprises a steel bolt.
 7. The seat attachment device of claim 1,wherein the interface surface of the first and second outer clampsfarther comprises one of a knurled surface and a set of teeth.
 8. Theseat attachment device of claim 7, wherein the first and second outerclamps are made of one of steel and an alloy.
 9. The seat attachmentdevice of claim 1, wherein the interface surface of the first and secondouter clamps each comprises a shoulder region.
 10. The seat attachmentdevice of claim 9, wherein the post has a first shoulder region and asecond shoulder region on an opposite side of the post from the firstshoulder region wherein the first and second shoulder regions of thepost are press fit against the shoulder regions of the first outer clampand second outer clamp in order to releasably secure the seat attachmentdevice to the post.
 11. The seat attachment device of claim 10, whereinthe shoulder region of the first and second outer clamps furthercomprise one of a knurled surface and a set of teeth.
 12. The device ofclaim 10, wherein the post further comprises a head portion having a setof teeth and the inner clamp mechanism has a set of teeth wherein thesets of teeth of the inner clamp mechanism and the head portion of thepost mesh with each other when the seat attachment device is releasablysecured to the post.
 13. The seat attachment device of claim 1, whereinthe inner clamp mechanism further comprises a first inner clamp and asecond inner clamp that are placed on opposite sides of the post. 14.The device of claim 13 further comprises a mechanism that maintains apredetermined distance between the first inner clamp and the secondinner clamp.
 15. The device of claim 14, wherein the mechanism furthercomprises one of an O-ring and a spring.
 16. The seat attachment deviceof claim 13, wherein the first inner clamp and the second inner clamprest on a head portion of the post.
 17. The seat attachment device ofclaim 1, wherein the post is made of one of aluminum, carbon fiber, andaluminum and carbon fiber.
 18. The seat attachment device of claim 17,wherein the inner clamp mechanism, the first outer clamp and the secondouter clamp are made of aluminum.
 19. The seat attachment device ofclaim 17, wherein the inner clamp mechanism, the first outer clamp andthe second outer clamp are made of carbon fiber with an aluminum insert.20. The seat attachment device of claim 1, wherein the inner clampmechanism is not bonded to the post.